There are mainly two types of scanner apparatuses; i.e., a flatbed-type shown in FIG. 9(A), which is suitable for reading books, magazines, or the like; and an ADF-type shown in FIG. 9(B), which can continuously read papers having a predetermined size and a sheet-like shape. The ADF-type is convenient in that it can automatically and continuously feed sheet-shaped documents having a predetermined size so as to perform reading processing. Nonetheless, it cannot read thick documents such as books and magazines. On the other hand, the flatbed-type can read thick documents such as books and magazines, however, the user must set the documents on the apparatus themselves and continuous reading cannot be performed. As described above, each of the flatbed-type scanner apparatus and the ADF-type scanner apparatus is suitable for some objects to be read, but not suitable for other objects to be read. For scanner users, a scanner apparatus having both the functions is desired.
Conventionally, there has been proposed a scanner apparatus which includes both a flatbed-type mechanism and an ADF-type mechanism as shown in FIG. 10 (see, for example, Patent Document 1). Such a scanner apparatus provided with both the flatbed-type mechanism and the ADF-type mechanism has the ADF mechanism mounted on the upper portion of the paper-pressing board of the flatbed unit in order to reduce the area occupied by the installed apparatus. The orientation of the shooter of the ADF mechanism is set and fixed so as to be easy to use for right-handed users with regard to convenience when setting the paper. Due to the position and orientation of the shooter of the ADF mechanism being set in this manner, there has been a problem in that convenience for left-handed users is sacrificed and freedom with regard to the place where the apparatus itself can be set is lessened.
Further, in a conventional scanning apparatus provided with both the flatbed-type and ADF-type mechanisms, the ADF mechanism is coupled or attached to the upper portion of the paper-pressing board of the flatbed mechanism. For this reason, when reading is performed with the flatbed unit, reading cannot be performed with the ADF unit and when reading is performed with the ADF unit, reading cannot be performed with the flatbed unit, so reading with both units cannot be coordinated.    Patent Document 1: Japanese Patent Application Laid-Open (kokai) No. 2000-295391